The new caste system makes the biggest impact on the gameplay. You should be able to achieve some tasks better with specific castes (and some worse
It depends on your view).
For example, if you want all your trees intact, you should keep obsidian dwarves away from woodcutting (and probably from outside military) because they can cause forest fires.
However if you don't care for the outside trees and/or use underground trees (and it's easier since now you can use "compact peat" as a new fuel source, and stone for beds) then you may want to encourage forest fires to keep aboveground critters away.
Another thing you should care about is that your dwarves should be trained in shields and dodging, because ranged weapons are stronger than in vanilla.
By the way, if you want the fun soil stuff (goethite as an iron ore in the soil, compact peat as the new fuel source) then you may want to pick a biome with a swampy soil (blanket mire/black bog/swamp peat).
Note that evil biomes are deadlier because they have raptors which are quite nasty.
Underground has some nasty/poisonous undeads and aberrations too, so be careful there, it's better to wall-off your first exposed cavern excavations.
Note that if you want to exploit the Altar of Nature which gives you seeds from vermin corpses, you may want to include a good biome in your Embark location, because moon berry seeds you get from those are plantable only in good biomes.
There're tons of ideas I can give you, but you can play without them and still have plenty of Fun
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P.S. Minor fix: on the DFFD page, the description says "For 0.31.06" not .08. Not in the info box, but in the description.
Thank you, I always keep forgetting about this.